I have an ODAC and I can't detect any noise unless I max-out the volume knob with my ER-6is. Not that it matters, since playing anything at that volume with tho

I have an ODAC and I can't detect any noise unless I max-out the volume knob with my ER-6is. Not that it matters, since playing anything at that volume with those headphones would be deafening and painful. I definitely hear more noise with my FiiO E7, and my laptop's headphone-out is even worse. In the hope that I have some idea of what I'm talking about, I've listed some possible reasons why you may be hearing noise and how to fix them. 1. Using analog inputs (RCA or line in) instead of USB. This will just amplify the noise from your input source. Analog inputs are enabled even if you're playing sound through USB, so be sure to disconnect any secondary source from your amp. 2. Nearby EMI. I found I could hear a high-pitched whining if I put my amplifier near the lower-right of my monitor. Repositioning your amplifier and/or headphone cable may fix the problem. 3. Grounding issue (unlikely). Try unplugging the amp's adapter and using the DAC-line output[1]. If there's no noise, the problem must be in amplification. That means either a defective amplifier circuit or a grounding/EMI issue. 4. Bad software (very unlikely). I once had a copy of VLC that output low-level noise when paused. This was when x86-64 was new. There were plenty of other problems with VLC on 64-bit at the time, since it used ints and longs as bitfields. You'd have this problem with all soundcards, not just the ODAC. It might also be useful to describe your set-up in more detail, including what headphones you've tried your amp with. Edit: Another thing you'll want to do to improve audio output: Make sure your OS is sending 24-bit audio to the ODAC. On OS X, open up Audio Midi Setup, then select the ODAC output and switch it to 24 bit. The default is 16-bit, which reduces dynamic range if you don't have the software volume at 100%. 1. It's the right-most output on mine: http://abughrai.be/pics/IMG_0594.JPG http://abughrai.be/pics/IMG_0594.JPG. I'm not sure where the DAC-out is on other versions.